The present invention relates generally to printing presses and more particularly to a signature transport device for transporting printed products.
A web printing press, for example for newspapers, will print a continuous web of material. In a folder of the printing press, the web will be folded, if desired, and then cut, so that signatures result. The signatures can then be conveyed on a conveyor and delivered for further processing, such as collation.
U.S. Pat. No. 4,482,141 discloses a method and device for conveying signatures from a blade chain conveyor supporting the signatures directly at a fold line. The signatures are gripped from above by orbitally-rotating clamping pads, which then transfer the signatures to a belt conveyor perpendicular to the blade chain conveyor.
European Patent Application No. 0771 675 A1 discloses a device for removing signatures from a saddle conveyor supporting the signatures. The conveyor has cutouts that permit the signatures to be gripped from above by a rotating clamping device, which then further conveys the signatures to a belt conveyor.
U.S. Patent Application No. 2001/00327741 discloses a device for removing signatures from a saddle conveyor that moves the signatures over cutouts in a sword. Grippers grip the outside of the signature from above and transfer the signatures to a further conveying device.
An object of the present invention is to permit efficient removal of signatures from a saddle conveyor.
The present invention provides a signature transport device comprising: a conveyor for moving a plurality of signatures in a first direction, and a rotary blade device having a first blade having an edge for lifting a first signature of the plurality of signatures from the conveyor, the edge being parallel to the first direction, and the first blade rotating about an axis perpendicular to the edge.
By permitting the blade to rotate while the edge remains parallel to the first direction, the edge can lift the signatures from the conveyor.
Preferably, the rotary blade device includes a second blade rotating about the axis. The first and second blades may be supported rotatably on a rotating arm rotating about the axis.
The arm preferably includes a first pulley rotatably supported on one end of the arm, the first pulley fixed to the first blade. A belt then is connected to a fixed pulley. As the arm rotates, the belt interacts with the fixed pulley to cause the first pulley to rotate so that the edge remains in a same orientation, i.e. parallel to the first direction. The second blade may also be fixed to a second pulley, which is rotatably supported on another end of the arm. More than two blades may also be provided.
Preferably, the belts are toothed on an interior surface, and the pulleys on an outer surface. The belts may have a smooth outer surface. An adjustment roller interacting with the outer surface may set the tension in the belt.
The conveyor preferably includes two parallel chains, and the first blade passes between the two chains to contact a fold of the signatures.
The present invention also provides a printing press comprising a print unit for printing a material, a conveyor for moving a plurality of signatures formed from the material in a first direction, and a rotary blade device having a first blade having an edge for lifting a first signature of the plurality of signatures from the conveyor, the edge being parallel to the first direction, and the first blade rotating about an axis perpendicular to the edge.
Preferably, the printing press is a web printing press, and further includes a folder for forming signatures from the web.
The present invention also provides a rotary blade device for interacting with printed materials comprising a rotating arm, a first pulley rotatably supported on the rotating arm, a first blade fixed to the first pulley, a fixed pulley and a belt connecting the first pulley to the fixed pulley so that as the arm rotates, the first pulley rotates with respect to the arm.
Preferably, the rotary blade device includes a second blade and a second pulley attached to the arm.